bahmutov / cyclope

Cypress DOM snapshots and consistent image diffing in the cloud

cyclope

Cypress DOM snapshots and consistent image diffing in the cloud

Blog posts

• Save The Page On Test Failure

Videos

• Cyclope: Save A Full Page With Styles If A Cypress Test Fails
• Use LocalStorage From Cypress Test To Set Initial Data
• Test Dragging Items
• Introduction to cy.session command

Course lessons

Testing The Swag Store

• Bonus 39: Save the entire HTML page on test failures

Install

Add this plugin to your project. Assuming Cypress is a dev dependency

$ npm i -D cyclope
# or if you prefer yarn
$ yarn add -D cyclope

Include the plugin from your support file or an individual spec file

// in cypress/support/index.js
// https://github.com/bahmutov/cyclope
import 'cyclope'

Include the plugin from the config file in Cypress v10

// cypress.config.js
const { defineConfig } = require('cypress')

module.exports = defineConfig({
  e2e: {
    setupNodeEvents(on, config) {
      // https://github.com/bahmutov/cyclope
      require('cyclope/plugin')(on, config)
      // IMPORTANT to return the config object
      // with the any changed environment variables
      return config
    },
  },
})

Include the plugin from the plugins file in Cypress v9

Include the plugin from your plugins file

// cypress/plugins/index.js
module.exports = (on, config) => {
  // https://github.com/bahmutov/cyclope
  require('cyclope/plugin')(on, config)

  // IMPORTANT to return the config object
  // with the any changed environment variables
  return config
}

Save the current page

If you need to save the current web application page, including any resources

// cypress/integration/spec.js
it('saves the page', () => {
  // normal Cypress commands
  cy.contains('.some-selector', 'some text')
    .should('be.visible')
    // when the app has reached the desired state
    // save the page in the folder "page"
    .savePage('page')
})

All local resources like images and CSS should be saved as local files. You can create a zip archive

// use .zip extension to zip the folder into a file
cy.savePage('page.zip')

When saving the zip, the function yields an object with filename, width, and height properties.

Options

• removeIframes (false by default) removes all <iframe> elements from the page before saving

cy.savePage('name', { removeIframes: true })

• ignoreFailedAssets (false by default) ignores failure in case part of assets can not be loaded

cy.savePage('name', { ignoreFailedAssets: true })

Save the failed page

This module includes a utility function to save the page if the test has failed. You can use this function as afterEach hook, probably from the support file, so it applies to all tests.

// in cypress/support/index.js
// https://github.com/bahmutov/cyclope
import { savePageIfTestFailed } from 'cyclope'
afterEach(() => {
  savePageIfTestFailed()
  // in case part of assets in your project is broken
  savePageIfTestFailed({ ignoreFailedAssets: true })
})

By default, the page is saved only in the non-interactive mode cypress run. If you want to save the page even when running in the cypress open mode, use the option saveInteractive

savePageIfTestFailed({ saveInteractive: true })

All pages are saved in the folder cypress/failed/<spec name>/<test name>.

Tip: store the cypress/failed as a test artifact on CI. If a test fails, download and open the folder/index.html to inspect the application's structure at the moment of failure.

cyclope

Alias clope

Generates consistent PNG image using external Cyclope image service. Requires CYCLOPE_SERVICE_URL and CYCLOPE_SERVICE_KEY environment variables when running Cypress. Supports hover

cy.get('#theme-switcher').realHover().cyclope('hover-over-sun.png')
// saves the generated "hover-over-sun.png" image
// equivalent
cy.get('#theme-switcher').realHover()
cy.clope()

If you want to simply skip DOM upload and image generation if the Cyclope service is not configured, set the Cypress environment option, for example using the cypress.json file

{
  "env": {
    "cyclope": {
      "skipUploadWithoutUrl": true
    }
  }
}

Debugging

You can enabled verbose debug messages in the terminal using the debug module by running the tests with the environment variable DEBUG=cyclope

$ DEBUG=cyclope npx cypress run

Examples

• todo-app-for-cyclope
• sudoku-mock-module

Small print

Author: Gleb Bahmutov <[e-mail]> © 2021

• @bahmutov
• glebbahmutov.com
• blog
• videos
• presentations
• cypress.tips

License: MIT - do anything with the code, but don't blame me if it does not work.

Support: if you find any problems with this module, email / tweet / open issue on Github

MIT License

Copyright (c) 2021 Gleb Bahmutov <[e-mail]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.